Closure valve for the oil port of a pressure accumulator



July 30, 1957 J. MERCIER v 2,801,067

CLOSURE VALVE FOR THE OIL PORT OF 'A PRESSURE ACCUMULATOR Filed oct. 25, 1951 56 9 155 iNvENToR ATTORNEYS United States Patent CLOSURE VALVE FR THE OIL PRT OF A PRESSURE ACCUMULATOR .lean Mercier, NewI York, N. Y.

Application October 23, 1951, Serial No. 252,750

12 Claims. (Cl. 251-50) This invention relates to a closure for the outlet port of a container for fluid and more particularly to a closure for the outlet port of a pressure accumulator of the type comprising a rigid container, to be filled with uids, usually oil and air under pressure and having a deformable partition intervening between such fluids.

When oil is pumped into the outlet port of the container on one side of the partition, the latter will be deformed further to compress the air on the other side of the partition. Where the closure device for the outlet port is a valve positioned in a tubular member axed in the outlet port of the accumulator and normally retained inlopen position, when a control valve connecting the accumulator to the hydraulic device to be operated is opened, the partition will expand toward its original shape to force the oil from the container through the normally open valve.

Where a rapid and profuse flow of fluid is required from the accumulator during any short period of time, such as for example, to operate a hydraulic brake, the flow of such uid would result in a low pressure area in the tubular member and a high pressure area in the container. As a result, the valve may close almost immediately after the flow of fluid begins, thereby to prevent proper functioning of the equipment to be operated. As the pressure in the system operated by the accumulator can be'no greater than the pressure in the container itself and generally will be less, even with the iiow of uid stopped, the Valve will remain closed with resultant ineffectiveness of the accumulator.

Where, to overcome this difficulty, the valve is designed to remain open even With a relatively great differential between the pressure in the container and the tubular member, if after substantially all of the`oil is discharged from the container the valve should still remain open, the partition may be extruded from the outlet with resultant rupture thereof and failure of the accumulator.

it is accordingly among the objects of the invention to provide a valve closure for the outlet port of a pressure accumulator of the above type, which valve closure has but few simple, sturdy parts that may readily be assembled and are not likely to become out of order and which valve closure will remain open even during profuse, rapid discharge of oil from the accumulator until substantially all the oil therein has been expelled, yet will'dependably close before the partition in the container can be extruded from such outlet port.

According to the invention from its broader aspect, the valve closure has a movable valve head normally in open position andladapted to be closed by pressure of the expanding partition'against said head as liquid is discharged from the container. Means are desirably provided independent of the valve head and associated therewith to equalize the pressure on both sides of the latter regardless of whether liuid is flowing through the tubular member in which the valve closure is positioned. Such means in the embodiment herein, desirably comprises a ICC chamber beneath the valve head adapted to be filled with uid as the container is initially charged and having such fluid retained under substantially the same pressure as exists in the container, as the fluid in the latter is expelled therefrom through the opened valve closure and the tubular member.

More specifically, according to one aspect of the invention, the valve closure is a poppet valve having its head resiliently retained in open position and according to another aspect of the invention the valve head is a liexible plate normally in open position and designed to bend to close the valve when the partition abuts thereagainst.

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

Fig. 1 is a longitudinal sectional view of an accumulator,

`Fig. 2 is a fragmentary sectional view similar to Fig.

l on a larger scale showing the poppet valve closure, and

Fig. 3 is a view similar to Fig. 2 of another embodiment of the invention.

Referring now to Figs. l and 2 of the drawings, the pressure accumulator desirably comprises a container or pressure vessel 11 preferably of strong rigid material such as steel, cast aluminum or the like, capable of withstanding high pressures. The container may be spherical or cylindro-spherical as desired and preferably has a deformable partition intervening between the inlet port 12 and the outlet port 13 of the container. Preferably the partition is a collapsible and expansible bag 14 which desirably is of resilient material such as rubber or synthetic plastic of like physical characteristics, which in distended but substantially unstretched condition is smaller than the cavity of the container and the inlet 12 leads into the rubber bag 14.

Means are desirably provided to close the outlet port 13. Such means desirably comprises an outlet closure assembly 15 including a tubular member 16 positioned in said port. Although any suitable means may be used to mount the tubular member 16, it is desirably so retained in port 13 that it may be removed therefrom without likelihood of injury to the mechanic disassembling the accumulator. To this end the construction shown'in Patent No. 2,469,171, dated May 3, 1949, is preferred. As shown, tubular member 16 desirably has an external annular flange 17 near the inner end thereof of Asmaller outside diameter than the diameter of port 13 and defining an annular shoulder 18. A locking member, illustratively a ring 21 of greater diameter than said port 13 and deformable to permit its insertion into saidV port, en- Compasses said tubular member 16 and is seatedV on the rim 22 of port 13, the inner diameter of said ring 21 being less than the outer diameter of iiange 17 so that said shoulder 1S mayl seat on said ring. Encompassing said tubular member 16 and in juxtaposition to port 13 is a rubber gasket or seal ring 23 which serves effectively to prevent leakage between port 13 and the side wall of tubular member 16 when a nut 24 isiscrewed on the externally threaded portion 25 of tubular member 16. i

The construction thus far described is not per se claimed herein as it is shown in the above mentioned patent.

According to the invention, the tubular member 16 has a wall 31 across its inner end, which wall desirably is substantially concave on its inner surface, as shown, and has an axial bore 32 therethrough. Desirably Vthe inner end of the cylindrical member 16 is of reduced diameter as at 33 defining a shoulder or seat 34 and has transverse passageways 35 therethrough providing communication between the container 11 and the bore 36 of said tubular member.

Slidably mounted in said axial bore 32 is a valve stem 37, desirably a stud, threaded at its upper end to coact with a correspondingly threaded axial bore 38 in an axial hub 39 of a valve head 41. The valve head 41 is desirably substantially cup-shaped and the substantially cylindrical Wall 42 thereof has an inner diameter slightly greater than theouter diameter` of the reduced inner end 33 ,of the tubular member so that it may encompass the latter, said wall 42 being of sufficient length so that its rim 43 may seat on the shoulder 34, to close the passageways 35. Means are desirably provided normally to urge the valve head 41 into the container so'that its rim 43 will'be spaced from the shoulder 34 to open the passage- Ways 35.'n Such means desirably comprises a coil spring 44 Vencompassingthe stud 37y and compressed between the adjacent faces of end wall 31 and valve head 41. Desirably the'spring is substantially in the form of a truncated cone and coacts at one end with an upstanding rim 45 about axial bore 32 and at its other end with a shoulder 46 formed in the 'valve head 41.

The valve head 41 and the end wall 31 of the tubular member Vdefine a chamber 47 therebetween which is in communication 'with the bore V36 of the tubular member 16 by means of substantially transverse inlets or passageways 48 through said end wall, the mouth 49 of each of said passageways being aligned respectively with thev passageways 35 through the side wall of tubular member 16, said `passageways preferably being longitudinally aligned, Vas shown, the mouth of each of said passageways 48 desirably being of area less than the cross sectional area of -the associated passageway 35.

In order to'limit the inward movement of the valve stem 37 and valve head 41 into the container under the urging of coil spring 44, the valve stemV 37 desirably has an enlarged portion or piston 51 at Vits outer end which coacts with the outer surface of end wall 31. Desirably, means are provided to prevent sudden impact of the enlarged portion. 51 against said outer'surface, which might cause sheering of such enlarged .portion with resultant inoperativeness of the valve. For this purpose the end wall 31 has a substantially cylindrical sleeve 53 desirably formed integral therewith coaxial with axial bore 32,'said sleeve having an internal diameter slightly more thanV that of the enlarged portion 51 of stem 37. Desirably `the stem 37 may move a distance suiicient to carry the piston 51 clear of the sleeve 53 so that oil or other uid may'iill such sleeve when the poppet valve is inrclosedposition.

Toruse the accumulator, the bag 14 is rst precharged with air'underpressure. As a result the valve head 41, against which the bag abuts, will be urged outwardly so that its rim 43 will seat on shoulder 34 to close the passageways 35. Simultaneously the piston 51 will be moved out of thepsleeve 53. When oil under pressure is forced through tubular member 16 in conventional manner, it will ll the sleeve 53 and also ow through transverse passageways 48 to ll the chamber 47. The pressure of the oil forced into said chamber 47, which is greater than the pressure in the pre-charged bag 14, will 'move the valve head 41 inwardly, thereby moving i Y the rim 43 thereof away from seat 34 to open passageways 35, As a result, the oil will ow through passageways 35 intothe container 11 to charge the latter and conipress the pre-charged bag 14.

V16 is opened. As a result the compressed bag 14 in the container 11 will force oil through open passageways 35 and through the tubular member 16 to the device to 'be operated. As the oil is under considerable pressure .member 16 is opened, the oil will ow at high speed in the container 11, it will pass through passageways V35 and tubular member 16 at relatively high velocity and consequently the pressure in tubular member 16 will be less than that in the container.

In the usual poppet valve construction, the coil spring is made of suiiicient strength to retainV the valve head in open position regardless of the differential in pressure between that in the container 11 and that in the tubular member 16 so that the desired quantity of oil may be discharged from the accumulator.

Flhe use of such a strong spring is undesirable in that it might prevent seating of the valve head 41 and closing of passageways 35 even when the expanded bag pressed thereagainst, which would permit extrusion of the wall of the bag through the passageways 35 with resultant puncturing of the bag and failure of the device.

The need for a strong coil spring is eliminated by the construction herein. During operation of the accumulator after it has been charged with oil as above described, and with the valve (not shown) controlling tubular member 16 in closed position, the bore of tubular member 16, the chamber 47 and the container 11 .will form a closed System, the pressure in which is determined by the compressed bag 14. Y

As the pressurein chamber 47 exerted against the outer surface of valve head 41 will be substantially the same as that in the container exerted against the inner surface ofthe valve head, but slight coil spring pressure is required to retain the valve head off its seat 34. `When the valve (not shown) controlling the tubular from container 11 through passageways 35 and tubular member 16 for discharge into the hydraulic system to' be operated. Y

Although such rapid ow of oil will cause the pressure in tubular member 16 to be less than that in the container 11, the valve head will not seat, for a portion of the oil owing at such high velocity through passageways 35 will be forced against the mouth 49 of passageway 48 .at substantially right angles thereto to maintain a pressure on the oil in chamber 47 that is substantially equal to the pressure in the container. Asa result, the slight coll spring pressure will be sufficient to retain the valve head in open position even with rapid ow through the valve closure. Y

- When Ythe oil'in the container 11 has been substantially exhausted and the expanded bag presses against valve head 41, the pressure in such bag will be slightly greater than the pressure in chamber 47 plus the coil spring pres,- sure and hence the rim 43 of the valve head 41 will be moved on seat 34 to close passageways 35Y before the wall of the bag can extrude therethrough.

Referring to the embodiment shown in Fig. 3, the means to close the outlet port 13 desirably comprises an outlet closure assembly 55 including a tubular member 56 positioned in said port andY retained therein desirably by the retaining structure shown in Figs. l and 2.

Positioned in said tubular member near the inner end thereof, is a web 57 having an axial Vhub 58 preferably formed integral therewith. The web desirably comprises a plurality of arms 59 extending radially outward from said hub andV aiixed at their ends to the inner wall of said'tubular member, said web desirably being formed integral with the latter. i

As shown in Fig. 3, the hub 58 desirably has a substantially cylindrical root end 61 and tapers outwardly therefrom to form a substantially frusto-conical Wall 62,

Y the rim 63 of which is illustratively shown extending beyondV the inner end 64 of tubular member 56 and is of diameter slightly less than Ythe inner diameter of said tubular member.Y Howeverit is to be understood that rim 63 could be at the same level as end 64 or slightly below the latter.V i

The hub SSYdesirablyvhas Va concavity 66 in its inner end offsuch contour that the rim 63 forms a relatively sharp edge, and an axial stem 67 in said concavity preferably formed integral with said hub, extends beyond said rim 63.

A valve head 68 in the form of a circular plate of flexible material such as metal is affixed on said stem preferably by means of a screw 69 extending through an axial opening therein and threaded in said stem.

The plate 68 is of diameter substantially equal to that of the outer diameter of tubular member 56 and its undersurface 70 is spaced from end 64 of tubular member 56 to dene a passageway 71 therebetween, the concavity 66 between the plate 63, the stem 67 and the hub S8 detining a chamber having the plate 68 as a wall thereof. The chamber 66 has an inlet 72 defined by plate 68 and rim 63, the area of the mouth of said inlet desirably being less than the cross sectional area of said passageway 71, said inlet being so aligned with said passageway that oil flowing therethrough will strike the mouth of said inlet at substantially right angles thereto. Desirably the periphery 73 of plate 68 is rounded to prevent injury to the bag 14 when the latter abuts thereagainst in the manner hereinafter to be described.

To use the accumulator incorporating the construction shown in Fig. 3, the bag 14 is first precharged with air under pressure. As a result, as the bag presses against plate 6%, the latter will be deformed until its periphery 73 presses against and seats on the inner end 64 of tubular member 56 to seal passageway 71 and inlet 72.

When oil under pressure is forced through tubular member 55 in conventional manner, it will flow through the spaces between arms 59 .of web 57 against the undersurface of plate 68. As the pressure of the oil is greater than that of the precharged bag l, the periphery 73 of plate 63 will be moved away from its seat 64 to open passageway 7i and inlet 72. As a result, the oil will flow through such passageway and inlet to charge container 1l, and compress the precharged bag 14 therein and also to charge chamber 66.

To'permit ow of oil from the accumulator to operate a device (not shown) connected thereto, a valve (not shown) controlling tubular member 56 is opened. AS a result, the compressed bag 14 in the Container 11 will force oil through passageway 71 and through the tubular member 56 to the device to be operated. As the oil is under considerable pressure in the container, it will pass through passageway 7l and tubular member 56 at rel..- tively high velocity and consequently the pressure in .tubular member S6 will be less than that in the container.

However, even though such rapid flow of oil will cause the pressure in tubular member 56 to be less than that in the container il, the periphery '.73 of valve plate 68 will not move onto its seat 64, for a portion of the oil flowing at such high velocity will be forced against the mouth of inlet 72 to maintain a pressure on the oil in chamber 66 that is substantially equal to the pressure in the container. As a result, the normal resistance to bending ofered by the plate 68 will be suicient to retain the periphery 73 of the latter olf its seat 64 to retain passageway 7l and inlet 72 open even with rapid flow of oil through the tubular member.

When the oil in the container il has been substantially exhausted and the expanded bag presses against plate 68, as the pressure in such bag will be slightly greater than the pressure in chamber 66 plus normal resistance to bending oiered by plate 68, it will cause bending of the latter. Hence, the periphery 73 of the plate 68 will be moved onto seat 64 to close passageway 71 and inlet 72 before the wall of the bag can extrude therethrough.

With the relatively simple constructions above described, a highly dependable valve closure is provided which will permit rapid flow of oil therethrough until substantially all of such oil is discharged and will reliably close the outlet port of the accumulator with substantially no likelihood of extrusion of the bag therein.

As many changes could be made in the above conf structions, and many apparently widely different ernbodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patentl of the United States is:

l. Valve means for controlling the flow of uid from the outlet port of a pressure accumulator of the type having a rigid container with an inlet port and a deformable partition intervening between said inlet and outlet ports, said valve means comprising a tubular member having a wall at its inner end with an axial bore there-V through, a valve head having a stem slidably mounted in said axial bore, said valve head and said end wall ydening a chamber therebetween, resilient means normally urging said valve head away from said wall, a passageway through said end wall providing communication between said chamber and the bore of said tubular member, and a passageway in the side wall of said tubular member providingr communication into the bore of said tubular member from the exterior of the latter, said passageways being aligned whereby the `iluid flowing through said passageway in said side wall into said bore in said tubular member will be directed against the adjacent inlet end of said passageway in said end wall.

2. The combination set forth in claim l in which means are provided to limit the inward movement of said valve head, said means comprising a sleeve on the outer surface of said end wall concentric with said axial bore and having an inner diameter larger than the latter and a piston at the outer end of said Valve stem of outer diameter greater than said bore and slidably mounted in said sleeve.

3. The combination set forth in claim l in which said resilient means comprises a coil spring, encompassing said valve stem and compressed between said end wall and said valve head.

4. Valve means for controlling the ow of fluid from the outlet port of a pressure accumulator of the type having a rigid container with an inlet port and a deformable partition intervening between said inlet and outlet ports, said valve means comprising a tubular member having a wall at its inner end with an axial bore therethrough, said tubular member being of reduced outer diameter at its inner end deiining an annular valve seat, a substantially cup shaped valve head having a stem slidably mounted in said axial bore, said valve head and said end wall deiining a chamber therebetween, said valve head having a substantially cylindrical wall of inner diameter slightly greater than the reduced inner end of said tubular member, resilient means normally urging said valve head in direction to retain the rim of said cylindrical wall spaced from said seat, a passageway through said reduced inner end of said tubular member providing communication between said chamber and the bore of said tubular member and a passageway in the side wall of said tubular member providing communication between the bore thereof and the exterior of said tubular member, said passageways being aligned whereby the liuid flowing through said passageway in said side wall into said bore in said tubular member will be directed against the adjacent inlet end of said passageway in said end wall.

5. The combination set forth in claim 4 in which said end wall has a concave inner surface and the passageway through said end wall extends transversely therethrough and is longitudinally aligned with the passageway through the side wall of said tubular member.

6. The combination set forth in claim 4 in which said valve head has an annular shoulder on the outer wall thereof and said end wall has an annular rim coaxial with said axial bore and said resilient means comprises a coil khaving a rigid container with an inlet port and a deformable partition intervening between said inlet and outlet ports, said valve means comprising a valve seat, a plate of resilient material rigidly atixed at its center Yand having its periphery normally spaced from' said valve seat, to dene a passageway, the periphery of said plate being movable against said Vvalve seatV to close said passageway,

' a wall beneath said plate, means mounting said wall in xed relation with respect to said valve seat, said plate and said wall'defining a chamber therebetween for uid, said chamber having an inlet in communication with said passageway, whereby the iiuid owing through said passageway will be directed against said inlet to create a pressure on the uid in said chamber.

V9. Valve means for controlling the iiow of iluid from the outlet port of a pressure accumulator of the type having a rigid container with an inlet port and a deform- ,able partition intervening between said inlet and outlet ports, said valve means comprising a tubular member dening a valve seat at its inner end, a web in said tubular member having a plurality of radial larms atlixed to the inner wall thereof and having an axial hub having its rim extending beyond said valve seat and of diameter less than the inner diameter of said tubular member, said hub having an axial projecting portion extending beyond said rim, a valve plate of resilient material affixed to said axial portion, said plate having a diameter greater than the inner diameter of said tubular member and having its periphery normally spaced from said rim and said valve seat to define a passageway into said tubular member, the periphery of said plate being movable against said valve seat to seal Vthe latter, a portion of said hub between the axis thereof and the rim being spaced from said plate, said portion and the associated portion of said plate defining a chamber therebetween for iluid, said chambervhaving an'inlet in communication with said passageway whereby the fluid flowing through said passageway will be directed against said inlet to create a pressure on the iluid in said chamber.

10. Valve means for controlling the flow of uid from the outlet port of a pressure accumulator,Y said valve means comprising a valve seat, a'valve head normally spaced from said seat to dene a passageway therebetween, a Wall between said passageway and the valve head, and means mounting said wall in fixed relation with respect to said seat, said wall and said valve head defining an enclosed pressure chamberV therebetween, said valve head being movable against said valve seat to close said passageway, said chamber having an inlet in communication with said passageway and against which inlet the liquid flowing through said passageway is directed to maintain the pressure in said chamber, thereby opposing the movement of said Valve head against said seat.

ll. The combination recitedsin claim 10 in which the inlet is so aligned with said passageway that the uid owing through the latter will strike the mouth of Vsaid inlet at substantially right angles thereto.

12. The combination set forth in claim llsin which the mouth of said inlet is of area less than the cross secs tional area of said passageway whereby only a portion of the fluid flowing through said passageway will be directed against the mouth of said inlet.

References Cited in the le of this patent UNITED STATES PATENTS 

